- Moderator
- #21
Jeff Kilgroe
Well-known member
Some are indeed teething problems, some are inherent issues with the specification. The current compatibility issues and device mix and match problems are definitely things that will be overcome as better chipsets and products enter the market. Or at least hopefully so. The high latency is here to stay, it's inherent in the design approach for USB. As for the adaptive speed leveling or dumbing-down the speed on a particular USB header to comply with slower devices, I'm not sure if that's part of the spec or not. I'm getting conflicting reports on that, but every host card I've tried so far is doing this... Not that I've tried many, but currently there's only two USB3 host chipsets on the market that I'm aware of.
With the relatively few devices on the market now that actually support USB3, I don't see the lack of it being a real burden at the moment, but for an integrated system like an iMac, not having it could shorten the lifespan of the system in the near future. I do somewhat wish that Apple would have introduced it with the latest round of iMac updates, but that's really just me desperately hoping for a faster connectivity option on those systems. Apple and Intel will both most likely add USB3 at some point. And I think they will eventually, regardless of how LightPeak shapes up, but Intel isn't always the first to jump on new connectivity standards like this. They tend to wait for it to mature and solidify somewhat. And with the current state of USB3, I wouldn't be incorporating it into a system now if there's no good way to update or guaranty proper functionality later. None of the current USB3 host options can provide any surety like that.... So makes perfect sense for Apple to ignore it for now.
USB3 does have a higher max throughput than 3Gbps SATA, but is obviously slower than 6Gbps SATA. Even with that, it still suffers from higher latency and greater operational overhead, so I would still prefer eSATA for any storage connectivity right now. Not only that, but eSATA is mature, proven and available everywhere. Which makes me wonder why Apple continues to ignore it.